After Angelina JolieexitedAlfonso Cuarón‘s 3D sci-fi thriller Gravity, the search for a replacement began. Last week, Latino Review learned that the producers behind the project were “interest[ed] in meeting Rachel Weisz for the role.” However, Deadline found out that Weisz was just one of the many names on the producer’s list of actresses they’ve talked to or screen tested: Sandra Bullock, Natalie Portman, Naomi Watts, Marion Cotillard, Carey Mulligan, Sienna Miller, Abbie Cornish, Rebecca Hall, Olivia Wilde, Scarlett Johansson and Blake Lively.

Now Risky Business has learned that Natalie Portman has been offered the role, as the studio approved the actress without requiring a screen test in the wake of the early Black Swan reviews. According to the report, Portman is expected to read the latest version of the script this week and make her decision shortly.

The project is written by his 28-year-old son, Jonás (The Shock Doctrine). Co-starring Robert Downey Jr, the $80 million film is a contemporary survival thriller that follows a woman as she attempts to make her way back to earth after a satellite crash sets off a chain reaction of further crashes. Because it’s set in space, most shots require every element to float in zero-gravity. Downey Jr will start production on Gravity in January, leave to shoot ‘Sherlock Holmes 2,’ and then return to finish with Cuaron. Sherlock 2 is scheduled to hit theaters for Christmas 2011, so we can probably expect to see Cuaron’s film in 2012.

A review of a year-old draft of the script gives some plot information from the film: Ryan, the character Jolie would have played, is not just the central role, but the only person on screen for a great deal of the movie. We’ve known that plans exist to have the opening shot be twenty minutes long, but the screenplay is formated in way that leads us to believe the whole film might take place in real time, with no cuts at all.

The script follows Ryan Stone, an engineer whose career path unexpectedly puts her on a space shuttle, doing repairs. (In a more recent draft, she’s working on repairing the Hubble.) She’s paired with veteran astronaut Matt Kowalski. But things go very wrong. The Russians just blew up something that “creates a chain reaction of spraying debris that hits multiple satellites, which also end up exploding, and all of a sudden thousands of pieces of debris are heading straight towards the space shuttle.”Cutting forward a bit, that debris destroys the shuttle and eventually leaves Ryan alone, trying to make her way to the International Space Station and rescue. ScriptShadow says:

Everything that can go wrong does go wrong as the movie becomes a series of near death experiences. Ryan must jump from point to point – whether it be to a vessel, a station, or an oxygen tank – and survive long enough to make the journey to the next point after that (and so on). Each destination is accompanied by dangerous debris, dropping oxygen, and the strong chance that whatever she’s trying to get to might not be there. Think Apollo 13, but with the odds stacked 1 million times higher against you, if that’s possible.

The entire film will be made at the UK-based effects company Framestore.

“In effect the film, as Avatar was, is 60% CG feature animation with the balance being hybrid CG and live action elements. Cuarón’s long and fluid style (the opening shot alone is slated to last at least 20 minutes) leaves no cut points to hide behind. In short, this is a hybrid of a fully animated, photo-real feature film with a blockbusting visual effects movie.”

Apparently the project was originally set up at Universal with Jolie attached but the studio put the project in turnaround, and it landed at Warner Bros with Harry Potter series producer David Heyman and Legendary Pictures. Cuarón is best known as the master filmmaker behind Children of Men, and he also helmed the best film in the Harry Potter series: Harry Potter and the Prisoner of Azkaban, as well as the classic Y tu mamá también.